Railway traffic controlling apparatus



Sept. 8, 1936. E. M. ALLEN RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed June 6, 1950 7 Sheets-Sheet l INVENTORY E filler],

' M ATTORNEY Sept. 8, 193.6. E, M ALLE 2,053,888"

RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed June 6, 1930 7 Sheets-Sheet 2 INVENTOR f'.

Sept 8, 1936. E. M.IIALLIEN V r 2 8 RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed June 6, 1930 7 Shets-SheetB INVENTORZY E .1). Allen,

ATTORNEY 'E. M. ALLEN RAILWAY TRAFFIC CONTROLLING APPARATUS Sept. 8,

Original Filed Jline 6, 1938* '7 Sheets-Sheet 4 INVENTORI E M -A/Ien,

U E CLRQCZZQQ E Al-Q ATTORNEY Sept. 8, 1936. E. M. ALLEN Q I RAILWAY TRAFFIC-CONTROLLING APPARATUS "Original Filed June 6, 1930 7 Sheets-Sheet 5 INVENTOR) E.l4 AIl n,

x Chi-1f L2: ATTORNEY Patented Sept. 8, 1936 UNITED STATES PATENT OFFICE RAILWAY TRAFFIC CONTROLLING APPARATUS Application June 6, 1930, Serial No. 459,435 Renewed March 29, 1932 62 Claims.

My invention relates to railway trafiic controlling apparatus for use on single track railroads over which traffic normally moves in both directions, and which are provided with passing sidings. More particularly, it relates to that class of systems wherein a despatcher located at a central oflice directs the movements of trains along the way by means of wayside signals or other devices, the despatcher carrying out the control of these wayside signals or other devices by means of selectively controlled relays located along the line.

The manner of controlling these relays located along the way may be as that of any of the well known systems such, for example, as disclosed in the Wallace Patent No. 1,650,575. The particular manner or controlling these relays form no part of this invention, and, for the sake of clearness, the control circuits therefor are not shown in the accompanying figures.

My invention resides in the manner of coordinating the wayside signals with the control exerted by the despatcher so as to bring about a unified trafiic despatching system. The operation of such a unified system as here proposed allows a much greater freedom of train movements between sidings, without limiting the use of the track between the two points, than that permitted by present systems. This unified control is also obtained without the use or any line wires. While this system provides the well known A. P. B. signaling protection, it further provides the checking of the stop indication of the signals governing opposing movements.

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

In Figs. 1 and 1 when placed together with the right-hand end of Fig. i adjacent the lefthand end of Fig. 1 is shown a stretch of single track railroad extending from a passing siding PI shown at left-hand end of the Fig. 1 through a passing siding P2 to a third passing siding P3 shown at the right-hand end of Fig. l In the Figs. 1 and l is shown a preferred manner of locating the wayside signals, it being understood, however, that my invention is in no manner limited to this particular arrangement of signals, and furthermore, that any number of signals could be located between passing sidings. Figs. 2 2 2 and 2 when placed end to end in the order named, constitute a diagrammatic view showing one arrangement of apparatus embodying invention as applied to the wayside signa'is shown in Figs. 1 and l and will be referred to in this description as Fig. 2. Fig. 3 is 2. diagrammatic view of the track circuits only for a track section such as a track section V of Fig. 2. Fig. 4 is a diagrammatic view of the track circuits only for use in connection with a track sec-, tion located between the opposite ends of a passing siding such, for example, as track section X of Fig. 2. Fig. 5 is a diagrammatic view of the track circuits only for a track section such as section W of Fig. 2. Fig. 6 is a diagrammatic view showing the control circuits only for relays associated with despatcher controlled signals such as signal R5.

In the Figs. 1 and 1 the trackway is shown divided into sections, each section being equipped with signals for governing trafilc in each direction. Each signal governing traflic from the left-hand end to the right-hand end is designated by the letter R with an exponent corresponding to the location. Each signal governing traffic from the right to the left is designated by the letter L with an exponent corresponding to the location.

These wayside signals may be of any of the well known types, and are designated here as of the colored light type. The despatcher controlled signals designated as RI, R5, R1, RI I, LIZ, L8, L6 and L2 each have three signal mechanisms, designated as A, B and C. Mechanism A is capable of displaying three indications proceed, caution, and stop. The mechanism B, in'the case of signals R5, RI I, L8 and L2, is capable of displaying two indications caution and stop. The mechanism B of the signals RI, R1, LIZ and L6 is capable of displaying only a stop indication. The signal mechanism C is what is commonly called call-on signal and is capable of displaying two indications call-on and stop. Signals R5, RI I, L8 and L2 with their opposing automatic signals are preferably located approximately 1000 feet in advance of the facing point switch over which they govern train movements; it is to be understood, however, that this distance can be varied to suit the local conditions. The signals RI R1 LI2 and L6 which govern the train movements from the various sidin'gs each have two mechanisms which are designated as D and E. The mechanism D is capable of displaying the three indications proceed, caution and stop. The mechanism E is a call-on? signal and displays either a call-on signal or a stop signal.

In the Fig. 2, the traffic rails I and 2 are insulated into track sections by insulated joints designatedby the. reference character 3. In the Fig. 2, each despatcher controlled relay is designated by the reference character HS prefixed by the reference character for the signal which this relay governs. For example, relay RBHS controls the signal mechanisms A and B of the signal R5. Each despatcher controlled relay governing a call-on signal is designated by the reference character OHS prefixed by the number designating the switch at which this relay is located. For example, relay 2CHS governs the call-on signals controlling the movements over the switch SW2. As stated above, the method of controlling these despatcher controlled relays forms no part of this invention. Suffice it to say, that, taking relay R5HS for an illustration, with the relay energized, the armatures I24, 23! and 232 are raised into contact with the front contacts I25, 233 and 234, respectively, while with the relay deenergized, these armatures drop into contact with their back contacts. All of the despatcher controlled relays of the system operate in a similar manner.

Each of the track sections is provided with a polarized track circuit. Referring to Fig. 4 in which is shown the track circuits for the section X of Fig. 2, it will be seen that at the right-hand end of the section a track relay TRXZ has one terminal connected to the rail I by conductor 349, back contact 34I of the despatcher controlled relay R1HS, armature 321, and conductor 342. The other terminal of this relay is connected to the rail 2 by conductor 343, back contact 344 of relay RlHS, armature 328 and conductor 345.

- At this same right-hand end of track section X,

a track battery TB1 is connected to the rails I and 2 by the following circuit: battery TB'I, conductor I4, back contact I5 of relay R1AI-I to be referred to later, armature I6, conductor I1, front contact I8 of relay RTHS, armature 328, conductor 345, rail 2, then across to rail I, conductor 342, armature 321, front contact 24, conductor 23, armature 22, back contact 2I, conductor 20 and back to the battery TB1. The positive terminal of battery TB1 may also be connected to rail 2 by a circuit consisting of conductor 26 branching 01f conductor I4, polar contact 31 of relay RTAH, polarized armature 33 in a position reversed to that shown in the figure, conductor 34, front contact 35, armature I6, conductor I1, front contact I8, armature 328, and conductor 345. The negative terminal of battery TB1 may also be connected to the rail I by a path consisting of conductor 3| branching from conductor 20, polar contact 36, polarized armature 28 reversed, conductor 29, front contact 39, armature 22, conductor 23, front contact 24, armature 321, and conductor 342. Furthermore, it is apparent that with the polarized armatures 28 and 33 of relay R1AH occupying the position as shown in the figure so as to be in contact with the polar contacts 21 and 32, respectively, the current supplied by the battery TB1 to the rails I and 2 is reversed in polarity. At the left-hand end of the section X, the track relay TRXI is connected to the rails I and 2 of the track section X in a manner similar to that described in connection with relay TRX2. Relay TRXI has one terminal connected to will by conductor 38, back contact 39 of the despatcher controlled relay LBHS, armature 40 and conductor M. The other terminal of relay TRXI is connected to rail 2 by conductor 42, back contact 43 of relay LBHS, armature 44 and conductor 45.

The track battery TBB located at the left-hand end of section, X has its positive terminal connected to rail 2 by conductor 46, back contact 41 of a relay LEAH to be referred to later, armature 43, conductor 59, front contact SI of the despatcher controlled relay LEHS, armature 44, and conductor 45. The negative terminal of battery TB5 is connected to rail i of section X by conductor 52, back contact 53 of relay LSAH, armature 54, conductor 55, front contact 56 of relay LBHS, armature 49, and conductor 4 I. The positive terminal of battery TBE is also connected to rail 2 by the circuit including conductor 48, conductor 51, polar contact 49, polarized armature 94 reversed to its position opposite of that shown in the figure, conductor 65, front contact 66, armature 48 in a raised position, conductor 50, front contact 5!, armature 44, and conductor 45. The negative terminal of track battery TB'd is connected to rail I by conductor 52, conductor 62, contact 51, polarized armature 59 reversed, conductor 60, front contact GI, armature 54, conductor 55, front contact 59 of relay LBHS, armature 40, and conductor 4|. Furthermore, it is apparent that with the polarized armatures 59 and 54 in contact with the polar contacts 50 and 83, respectively, that the current supplied by the track battery T135 to the rails I and 2 of section X is of reverse polarity. All track sections located between the opposite ends of a passing siding are to be equipped with track circuits similar to those just described in connection with the track section X of Fig. 4.

Referring now to Fig. 3, in which is shown the track circuits for the track section V of Fig. 2, it will be seen that the track relay TRV2 has one terminal connected to the rail I at the righthand end of the section V by a conductor 348, back contact 341 of a relay R98 to be referred to later, armature I01, conductor I98, back contact I09 of the track relay TRUI associated with the track section at the right of section V, armature 96, conductor 349, front contact 350 of a track relay TR9 associated with an insulating track section to be later described, armature 35L and conductor 91. The opposite terminal of the relay TRV2 is connected to the rail 2 by conductor 352, back contact 353 of relay RSS, armature I09, conductor IOI, back contact I92 of relay TRUl, armature I03, conductor 354, front contact 355, armature 356, and conductor I04. At this same right-hand end of track section V, there is located the track battery TB9 which has its positive terminal connected to the rail 2 by a conductor 98, front contact 99 of relay R9S, armature I09, conductor IBI, back contact 92, armature I93, conductor 354, contact 355, armature 356, and conductor I04. The negative terminal of the track battery TB9 is connected to the rail I by conductor I55, front contact H36 of relay RBS, armature I51, conductor I08, back contact I89 of relayTRUI ,armature 96, conductor 349, front contact 350 of relay TR9, armature 35I, and conductor 91. The positive terminal of battery T139 is connected to rail I by a circuit consisting of conductor 94, front contact 95 of track relay TRUI, armature 95 in its raised position, conductor 349, front contact 350, armature 356, and conductor 91. The negative terminal of the track battery T139 is connected to the rail 2 by a circuit consisting of conductor H9, front contact III of relay TRUI, armature I83 in its raised position, conductor 354, contact 355, armature 356, and conductor I04. At the left-hand end of the track section V, the track relay TRVI is connected across the rails I and 2 at the left-hand end of the section V, with one terminal connected to rail I by conductor 384, armature 385 of relay LBGP to be later described; conductor 386, back contact 381 of a despatcher controlled relay L8HS, armature 81, conductor 88, back contact 89 of a despatcher controlled relay 3CHS, armature 99, and conductor 9|, while the other terminal of relay TRVI is connected to rail- 2 by conductor 38!], armature 381, conductor 382, back contact 383 of relay L8HS, armature 15, com ductor 16, back contact 11 of relay 3CHS, armature 18, and conductor 19. The track battery T138 located at the left-hand end of track section V has its positive terminal connected to the rail 2 by either of two paths. First, conductor 16, back contact 1| of relay LBAH, armature 12, conductor 13, front contact 14 of the despatcher controlled relay LBHS, armature 15 to its raised position, conductor 16, back contact 11 of relay 3CHS, armature 18, and conductor 19. The second path branches from conductor 13 and extends along conductor 86, front contact 8I of the despatcher controlled relay 3CHS, armature 18, and conductor 19. The negative terminal of track battery T38 is connected to the rail I by either of two paths. First, conductor 82, back contact 83 of relay L8AH, armature 84, conductor 85, front contact 86 of relay LBHS, armature 81, conductor 88, back contact 89, armature 96, and conductor M. The second path branches from conductor and extends along conductor 92, front contact 93 of the despatcher controlled relay 3CHS, armature 96, and conductor 9i Furthermore, it is apparent that with the armatures 12 and 84 of the relay LBAH raised into contact with the front contacts 25 and I9, respectively, that the current supplied by this track battery T138 to the rails of the section V is reversed in polarity. All track sections of this system similarly located as the track section V are to be equipped with track circuits as shown in the Fig. 3, as just described.

In the Fig. 5 is shown the track circuits only for a track section adjacent the switch of a passing siding such as track section W of Fig. 2. At the right-hand end of the section W, the track relay TRWZ is connected across the rails by the conductors 358 and 359. At the left-hand end of the track section W, the track battery L131 normally has its positive terminal connected to the rail 2 by conductor 36!], back contact 36I of the track relay TRX2 associated with the track circuit X, armature 362, and conductor 363, and its negative terminal is normally connected to the rail 1 by conductor 368, back contact 369 of relay TRX2, armature 316, and conductor 31 I. The positive terminal of battery LB1 is also connected to rail 2 by a path branching from conductor 360 and extending along conductor 360 polar contact 364 of relay TRXZ, polarized armature 365 reversed to its position opposite from that shown in the figure, conductor 366, front contact 361, armature 352, and conductor 363. Likewise the negative terminal of track battery LB1 is connected to the rail I by a path extending from conductor 368, polar contact 312, armature 314 of relay TRXZ in its reversed position, front contact 315, armature 316 in its raised position, and conductor 31I. It is evident that with the relay TRX2 energized, so as to raise its neutral armatures 362 and 310, and its polarized armatures 365 and 314 occupying the position as shown in the figure, thereby making contact with contacts 316 and 311, respectively, that the current supplied by the track battery LB1 is reversed in polarity.

All track sections of the system similar to the track section W are to be equipped with track circuits similar to that described in reference to track section W.

Referring to the Fig. 2, at all intermediate signal locations, such as locations designated by the reference characters 9 and I6, a short insulated section is located between the two opposing automatic signals. This track section is preferably about 66 feet in length. This short insulated track section is provided with a track circuit consisting of a battery connected across the rails at one end of the section and a track relay connected across the rails at the opposite end.

Each of the despatcher controlled signals has associated with it certain control relays. Referring to the Fig. 6, the despatcher cont-rolled signal R5 has associated with it the control relays R5AH, R5BI-I and RECH. The relay REAH is associated with the signal mechanism A. The relay R5BH is associated with the signal mechanism B, and the relay R5CH is associated with the signal mechanism C of signal R5. The circuit for the relay RSAH consists of the following elements: battery LB6, conductors I44 and I20, front contact I2I of a relay LiiGP, armature I22, conductor I23, armature I24 of the despatcher controlled relay REHS, front contact I25, conductor I26, front contact I 21 of the track relay TRXI for the track sect-ion X, armature I28, conductor I29, polar contact I36 of a relay KRZ associated with the switch SW2 in a manner to be later described, polarized armature I 3|, conductor I32, armature I34, contact I35, conductor 536, contact I31 of the track relay TRY for the section Y, armature I38, conductor I39, coils of the relay R5AH, conductor I 43, armature I II of the track relay for the section Z, back contact I42 and conductor I43 to the opposite terminal of the battery LB6. It is to be noted that to complete this circuit for the relay RSAH that the despatcher controlled relay R5HS must be energized to close the contact I25, that the track relays TRXI and TRY for the track circuits in advance of the signal R5 must both be energized to close the front contacts I21 and I31, respectively, and that the track relay TRZ2 for the track section in the rear must be deenergized to close the back contact I 42; The circuits for energizing the relay RBBH consists of the following elements: battery L136, conductors I44 and I20, contact I2I, armature I22, conductor I23, armature I24 of the despatcher controlled relay REHS, front contact I25, conductor I26, conductor I51, polar contact I58, polarized armature I59 of the relay KR2 reversed to its position opposite from that shown in the figure, conductor I69, armature I6I, front contact I62, conductor I 63, contact I64 of the track relay TRY, armature I65, conductor I66, armature I61, back contact I68 of the relay R5AH, conductor I69, coils of the relay R5BH, conductor I16, conductor I46, armature MI, back contact I 42, and conductor I43 back to battery LE6. The circuit for energizing the relay RBCI-l' consists of the following elements: battery LBS, conductor I44, conductor I11, front contact I18 of the relay KR2, armature I19, conductor I86, frontcontact I8I of the despatcher controlled relay 2CHS, armature I82, conductor I83, armature I 84 of relay R5AI-I, back contact I85, con ductor I 86, armature I61 of the relay R5BH, back contact I88, conductor, I89, coils of the relay R5CH, conductors I and I49, armature I4I, back contact I42 and conductor I43 to battery LBBY Referring now to Fig. 2, the relay KRZ associated with the switch SW2 is energized so that its armatures occupy the position shown in the figure by a circuit from positive battery to a circuit controller operated by the switch SW2, through the coils of the relay and back to the negative battery. With the switch SW2 reversed so as to reverse the position of the circuit controller associated therewith, then relay KR2 is energized so that its polarized armatures occupy the position opposite to that shown in the Fig. 2. It is therefore to be noted that with the switch SW2 set for main track movements, the circuit for the relay RSAH is held closed at the polar contact I39, of relay KR2, while with the switch SW2 set for movements for the passing siding then the circuit for the relay RSBH is held closed at the polar contact 559 of relay KR2. It is also to be noted that with the switch occupying either of its extreme positions, that the circuit for the relay RECH is closed by the neutral armature I19 of the relay KRZ. The relay REGP is associated with the relays RSAH, RSBH and R5CH. The circuit for energizing this relay R5GP consists of the following elements: battery LBS, conductors |29, I44 and I91, armature I98 of relay R5AH, back contact l99, conductor 209, armature 20| of relay R9135, back contact 202, conductor 293, armature 284 of relay R5CH, back contact 205, conductor 296, coils of the relay RSGP, and conductor M3 back to battery. That is to say, the relays R5AI-I, REBH and RSCH must each be down before R5GP is energized. All despatcher control signals governing train movements approaching a passing siding have associated with them relays controlled in the same manner as just described in reference to Fig. 6, and each switch of this system has associated with it a circuit controller and a relay similar to that described in connection with the switch SW2.

Referring again to the Fig. 2, and looking at the despatcher controlled signal R1, it will be seen that this signal has associated with it the control relays R'ZAH and R'JCH. The circuit for energizing he relay R'EAH to operate its polar contacts to the left extends from the positive terminal of battery LB1 along conductor 2| 6, back contact 2| i of the track relay TR'v'l for the tracksection V, armature 2|2, conductor 2E3, coil of the relay RiAI-I, conductor 209, polar contact 2|4 of relay KR3, polarized armature 2 l5, front contact 2|1, armature 2|8, conductor 2|9, front contact 220 of the despatcher controlled relay RlHS, armature 22|, conductor 222, armature 223 of the track relay TRW2, conductor 224, armature 225 of the relay LSGP, conductor 229, armature 221, back contact 228, and conductor 299 back to battery. With the track relay TRV i energized and its armatures 2|2 and 221 raised into contact with the front contacts 229 and 230, respectively, then the current supplied by the battery LB1 to the relay RlAi-I is reversed in polarity to operate the polar contacts to the right, as shown. The circuit for energizing the R'ICH relay extends from battery LB1 along conductors 2|0 and 240, armature 24| of relay KR3, conductor 242, front contact 243 of the despatcher controlled relay 3CHS, armature 244, conductor 2 35, polarized armature 246 of relay KR3, contact 241, conductor 248, armature 249 of relay RlAl-I, back contact 250, conductor 25L coils of relay R1CH, and conductor 252 back to battery LB1.

A signal R1 at the location 1 governs the traflic from the siding towards the right-hand end in Fig. 2. This signal R1 has associated with it the control relays RTDH and R1EH. The circuit for energizing the relay R1DH consists of the battery LB1, conductor 2|0, back contact 2|| of track relay TRV|, armature 2|2, conductor 2|3, conductor 219, coils of the relay R'lDI-I, conductor 21|, polar contact 212, polarized armature 2|5 when occupying position reversed to that shown, contact 2|1, armature 2| 8, conductor 2|9, front contact 229 of a despatcher controlled relayRil-IS, armature 22|, conductor 222, armature 223, conductor 224, armature 225, conductor 226, armature 221, back contact 228, and conductor 299 back to battery. It is to be noted that the circuit for the control of this relay RIDI-I is the same as that traced for the relay R1AH except that the circuit for R1DH passes through the right-hand contact 212 of the relay KR3, whereas the circuit for the relay R1AH passes through the left-hand contact 214 of the relay KR3. The relay R'lEI-I is energized over the following circuit: battery LE1, conductors 2H] and 240, armature 2M, conductor 242, front contact 243 of the despatcher controlled relay 3CHS, armature 244, conductor 245, polarized armature 246, right-hand contact 213 of relay KR3, conductor 214, armature 215, back contact 216, conductor 211, coils of the relay RlEH, conductors 218 and 252 back to battery. All signals governing train movements away from a passing siding are associated with control relays similar to those described in connection with the signals R1 and R1 Each of the intermediate automatic signals is associated with a slow-releasing relay and a stick relay. Referring to the automatic signal R9 of Fig. 2, for example, the slow-releasing relay RQH is energized by the following circuit: battery LB9, conductor 231, armature 239 of the track relay TRUI for the track section U in advance of the signal R9, front contact 295, conductor 295, coils of relay B9B, and conductor 291 to battery. The stick relay R98 associated with this signal R9 has the following pick-up circuit: battery LE9, conductor 231, armature 238 of track relay TRUI back contact 298, conductor 299, armature 300 of the track relay TR9 for the short insulated section between the automatic signals R9 and L9, back contact 301, conductor 302, armature 303 of the stick relay L9S associated with the opposing automatic signal L9, back contact 304, conductor 395, armature 301 of the slow-releasing relay RSI-I, front contact 398, conductor coils of the relay RQS, and conductors and 291 to battery. The holding circuit for this stick relay R9S branches from the conductor 299 and extends along conductor 3l0, armature 3| its own front contact 3 i2, conductors 3|3 and 306, coils of the relay R93, back to battery.

Attention is here called to the control exerted by this stick relay R9S. It was described in connection with Fig. 3 that the connections of the track relay TRV2 to section V pass through the back contacts 341 and 353, and that the track battery TBS is connected to the rails of section V through the front contacts 99 and I06 of R98 when the track relay TRUI is down. It is to be noted that the polarity with which TB9 is thus connected to the section V is reversed to that prevailing when track relay TRUI is up. It is to be understood that the polarity prevailing when relay TRUI is up retains the polarized armatures of relay TRV| in the position as shown in the Fig. 2. Therefore, with track relay TRUI down and stick relay RQS up and the polarity of the current from TB9 reversed, then the polarized armatures of track relay TRV| are reversed from the position as shown in Fig. 2.

Referring to the signal R5 in Fig. 2, the circuit for displaying a proceed signal extends from positive side of battery LBS along conductors I28 and I4 8, armature I45 of the control relay R5AH, front contact I 56, conductor I41, armature I48 of the track relay TRY, front contact I 49, polarized armature I58, right-hand contact I53, conductor E54, proceed light A and to common battery. The circuit for displaying a caution signal is the same as that just traced for the proceed signal up to the polarized armature I50, then polarized armature I55 in the left-hand position, contact I5I, conductor E52, caution light A and to common battery. The circuit for displaying a stop signal is the same up to the armature I45 of the control relay R5AH, then along back contact I55, conductor I56, stop light A and to common battery. The circuit for displaying a caution signal by the signal mechanism B of the signal R5 extends from positive side of battery LBli, conductors I20, I44 and HI, armature I12 of the control relay R5BH, front contact H3, conductor I14, signal light B to common battery. A circuit for displaying a stop signal by the mechanism B is the same as that just traced up to armature I12 of the control relay R5BH; then along back contact I15, conductor I16, signal light B and to comnoon battery. A circuit for displaying a call-on signal by the signal mechanism C of signal R5 is from battery LB6, conductors I and I8I, armature I92 of the control relay R5CI-I, front contact I93, conductor I 94, call-on signal light C and to common battery. A circuit for displaying a stop signal by the call-on mechanism 0 of signal R5 is the same as that just traced up to armature I92, then back contact I95, conductor I85, signal light C and to common battery. All signals similar to the signal R5 have signal light circuits similar to those just traced for signal R5.

Referring now to the signal R1 the circuit for the proceed light A is from positive side of battery LB1 along conductor 253, armature 254 I of the control relay R'IAH, front contact 255,

polarized armature 256 in the right-hand position, contact 259, conductor 250, signal light A and to common battery. The circuit for the caution signal light A is the same as that just traced up to the polarized armature 256, then with polarized armature 255 in the left-hand position, it extends along contact 251, conductor 258, caution light A and to common battery. The circuit for the stop signal light A branches from the armature 254 in a down position, back contact 2&5, conductor 262, signal light A back to common battery. The circuit for the call-on signal C of signal R1 is from battery LB1 along conductors 253 and 264, armature 265 of the control relay RlCI-I, front contact 266, conductor 2%, signal light 0 and to common battery. The stop light C for signal R1 extends from the armature 265 of relay R'lCH in a down position, back contact 268, conductor 269, signal light C and to common battery. The circuit for the proceed signal light D of the signal R1 extends from positive side of battery LB1 along conductors 253, 264 and 219, armature 280 of the control relay RlDH, front contact 28I, polariced armature 282 in the right-hand position, contact 285, conductor 261, signal light D and to common battery. The circuit for the cauticn light D is the same as before up to polarized armature 282, then with armature 282 in the left-hand position, contact 283, signal light D and to common battery. The circuit for the stop light D branches from the armaturei280 along back contact 281, conductor 288, signal light D and tocommon battery. A circuit for the call-on signal light E of the signal R1 branches from the conductor 219 and extends along conductor 238, armature 290 of the control relay R1EH, front contact 29I, conductor 2%, signal light E and to common battery. A circuit for the stop light E2 extends from armature 298 in a down position along back contact 293, conductor 294, signal light E and to common battery.

In describing the operation, let us first assume that a train is to be allowed toproceed from the left to the right in the Fig. 2, taking the case Where the despatcher desires to have this train move from section Z past the siding P2 to the next passing siding P3, and where there is no other train occupying any of the intervening track sections. The despatcher by energizing the despatcher controlled relay RI I HS raises the armatures 32! and 322 of the relay RIIHS to disconnect the track relay TRTZ from the rails of the section T and to connect to these rails the track battery 'IBI I, in the same manner as was described in connection with the circuits controlled by the relay R5HS. Current from the battery 'IBI I thus energizes the track relay TRTI located at the left-hand end of the section T, and the energizing of the track relay TRTI disconnects the track relay TRU2 from the rails of the section U and connects thereto the track battery TBH). The track battery 'IBI 0 will then, in turn, energize the track relay TRUI located at the left-hand end of the section U. The track relay TRUI, in turn, disconnects the track relay TRVZ of section V, and connects to the track the track battery TBS, and the track battery TBS will then energize the track relay TRVI. Now the energizing of the track relay TRTI closed the circuit for the caution light of the automatic signal RIO, and the energizing of the track relays TRUI and TRVI closed the proceed light circuits for automatic signalsRB and R8, respectively. a

It will be seen, therefore, that signal R8 is controlled over a tumble-down circuit comprising a series of link circuits, of which one is illustrated in Fig. '3, there being a link circuit for each intermediate section'for each direction. Thus the link circuits controlling signal R8 are the track circuits including relays TRTI, TRUI and TRVI, respectively, the energization of the first link circuit being controlled by relay RI IHS and that of each remaining link circuit by the relay of the next link circuit in advance. The circuits for the two directions are similarly arranged, and it follows that signal LII, which corresponds to signal R8 for traffic movements in the opposite direction, has a tumble-down circuit controlled by relay'L8HS, the link circuits in this. case being the track circuits which include relays TRV2, TRUZ and TRT2, respectively.

It will be readily apparent from the drawings that the link circuits are interlocked so that if one tumble-down circuit is energized all the links of the other tumble-down circuit are deenergized, back contacts of each relay such as TRUI, for example, being included in the circuit for the relay, such as TRVZ, of the adjacent link circuit for the opposite direction. i

Returning to the description of the operation, it is to be noted that the despatcher upon energizing the relay RI IHS also raised the armature 320 to close the circuit for the control relay RI IAH in the same manner as was described in connection with the relay R5HS and the energizing of the relay RI IAH closed the circuit for the proceed or caution signal light of mechanism A of signal RI I, and also reversed the polarity of the current supplied to the rails of section T to cause the indication of signal RII'I to change from caution to proceed. Again, the energizing of the track relay TRTI also closed the circuit for the slow-releasing relay RIOH, and likewise at signal R9, the energizing of the track relay TRUI closed the circuit for the slow-releasing relay RSH. The despatcher after energizing relay RI IHS must next energize the relay R'IHS. Since relay TRVI is now energized, the closing of contact 22I of relay R'IHS will cause the enenergization of relay R'IAH to light lamp A so that signal R'I will indicate proceed. The lifting of the armatures 321 and 328 of relay R'IHS disconnects the track relay TRXZ from the righthand end of the rails of the section X and connects thereto track battery TB'I, with the result that the battery TB'I energizes the track relay TRXI located at the left-hand end of the section X. The despatcher will then next act to energize the relay R5HS, and the lifting of the armatures 23I and 233 of relay R5HS will disconnect the track relay TRZ2 from across the rails of the track section Z, and to connect thereto the track batttery T85. Also, the energizing of the relay RSHS by the despatcher closes the control circuit for the relay R5AI-I at the contact I25. Relay R5AH will now be energized by the circuit traced in connection with Fig. 6 and it will, in turn, close the proceed circuit to A of R5 with the result that a proceed signal is displayed by the mechanism A of the signal R5. The train can now'proceed from the left-hand end of Fig. 2 to the passing siding P3 at the right-hand end of Fig. 2 with a proceed signal displayed by each of the successive signals. It will be apparent that as the train proceeds and enters the successive track sections, that the signal at the entrance of each section will display a stop signal to the rear of the train. It is to be noted that in the clearing of the signals for the movement of the train from the left to the right, that the circuits for all the opposing signals were opened to thereby insure the display of a stop signal for an opposing train movement. Next let us assume that the despatcher wishes to permit a second train to follow this first train from the left to the right in Fig. 2. The despatcher by retaining the control relays RI IHS, RIHS and R5I-IS energized will cause the signals to the rear of the first train to clear as the first train advances. In connection with the clearing of the signals for this second train, it is to be noted that at the intermediate signals, a permissive signal is given to the following train by means of the slowreleasing and stick relays. Taking, for example, signal R9, as the first train shunts the rails of the short section and drops the relay TR9, and then advances into the section U and shunts the rails to deenergize the track relay TRUI, the stick relay RES is energized by the pick-up circuit previously traced and which circuit passes through the back contact 3DI of relay TR9, the back contact 298 of the relay TRUI, and the front contact 308 of the slow-release relay RQH, inasmuch as this circuit remains closed during the slow-release period of relay RSH. The stick relay R96 is then retained energized through its own contact 3I2 and the back contact 298 of the track relay TRUI. The energizing of this stick relay RBS acts to retain the track battery TBQ across the rails of the track section B by the closing of its front contacts 39!) and 39I, during the time that the track relay TRUI is shunted by the train in the section U. The polarity with which the track battery TBS is thus connected to section V is such as to reverse the track relay TRVi and thereby cause the signal R8 to display a caution indication.

Next, let us assume that there is a first train to the left of the signal R5 and that it is moving to the right, that the dispatcher has deenergized relay R5 I-IS and has energized relay Li2HS and that there is a second train travelling to the left from the passing siding P3 to the passing siding P2, and that the despatcher has reversed the switch SW3 in order that this second train moving from right to left may move into the passing siding P2 to clear the first train. The despatcher by energizing relay LSHS will cause the B mechanism of the signal L8 to display a caution signal, inasmuch as the KRS relay is now reversed, and the energization of the relay LBHS will also connect the track battery TBB across the rails at the left-hand end of the track section V, and then, in turn, battery will be connected at the left-hand end of each successive intermediate section, to thereby clear the L signals for the train approaching the pwsing siding P2 from the right. The despatcher, even though he energizes the relay RSI-IS, can not energize the control relay REAH through the contact I25, inasmuch as there is no track battery connected across the rails of the section X, and thus the track relay TRXI remains down to hold the circuit for REiAI-I open at front contact I21. However, the despatcher can advance the train mov ing from the left to the right past the signal R5 by energizing the control relay ZCHS. The energizing of this relay ZCHS by the despatcher will place battery across the rails of section Z and will close the circuit for the control relay R5CH, and the energizing of the relay R5CH, in

turn, will close the circuit for the call-on sig-.

nal C at R5, with the result that the train from the left can advance to the signal R1 at which point it will receive a stop signal until the train moving from the right has passed into the passing siding P2 and the despatcher clears the R signals.

i'he moving of a train from the right-hand end of Fig. 2 to the left-hand end will take place in a manner similar to that described in connection with the train travelling from the left to the right. It is to be noted that a train proceeding out of a passing siding will receive the same protection as the train advancing on the main track. To illustrate, a train on the passing siding P2 and moving to the right will receive the same protection by the signal R7 as it would receive were it on the main track and advancing to the right past the signal B1. In switching in and out of any of the passing sidings, the despatcher has control of the movements through the medium of his relay CH8 and the call-on signals.

Although I have herein shown and described only one form of apparatus embodying my inventic it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from. the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of single track arranged in track sections; at least one of said track sections provided with two normally deenergized track circuits, one circuit associated with each direction of trailic; a signal normally indicating stop located at each end of the stretch to govern traific in opposite directions through the stretch, a control circuit for each signal having two normally open contacts, means responsive to the energization of the track circuit associated with the direction of trailic which is governed by a signal for closing one of the said open contacts of the control circuit of that signal, a first means controlled from a central despatching of ice for closing the second open contact of said control circuit, a second means controlled from the central despatching ofiice to effect the energization of the said track circuit, and means to prevent the energization of a track circuit unless the track circuit associated with the opposite direction of traffic remains deenergized.

2. In combination, a stretch of single track arranged in track sections; a plurality of track sections each provided with two normally deenergized track circuits each having a track relay, one circuit being associated with each direction of trafiic; a signal normally indicating stop located at each end of the stretch to govern traffic in opposite directions through the stretch, a signal relay for each signal rendered effective to clear the respective signal upon the energization of all of the said track relays of the stretch associated with the direction of traffic which is governed by that signal, and means controlled from a central despatching ofiice to bring about the energization of the said track relays, said means acting to first energize the most advance track circuit associated with the direction of traffic governed by the signal and then each successive track circuit in turn.

3. In combination, a stretch of single track arranged in track sections; a plurality of track sections each provided with two normally deenergized track circuits each having a track relay, one circuit being associated with each direction of trafiic; a signal normally indicating stop lo-- cated at each end or" the stretch to govern traflic in opposite directions through the stretch, a signal relay for each signal rendered efiective to clear its respective signal upon the energization of all of the said track relays of the stretch associated with the direction of traffic which is governed by that signal, means controlled from a central despatching office to bring about the energization of the said track relays associated With the direction of traflic governed by the signal, said means acting to first energize the most advance track circuit associated with direction of trafiic governed by the signal, and then each successive track circuit in turn, and means to prevent the energization of a track relay unless the opposing track relay of the track section remains deenergized.

4. In combination, a stretch of railway over which trafific normally moves in both directions including a first passing siding, intervening track and a second passing siding, a signal to govern a train leaving the first passing siding for the second passing siding, and normally indicating stop, a second signal to govern a train leaving the second passing siding for the first passing siding and normally indicating stop; two sets of normally deenergized track circuits for said stretch, one set associated with each direction of trafiic and adapted when energized to clear the signal for the respective direction of traiiic, and means controlled from a central despatching oihce to effect energization of one set or the other of said track circuits, said means acting to energize the most advance track circuit of the set and then each successive track circuit of said set.

5. In combination, a stretch of single track, signals located at intervals for governing traffic in one direction through the stretch and other signals located at intervals for governing traiiic in the other direction through the stretch, a track relay for the control of each signal, a circuit for each track relay each of which circuits includes a front contact of the track relay for the next signal in advance governing traffic in the same direction, a branch for each track relay circuit around the front contact of the track relay which controls such circuit, and means controlled automatically by the direction of traflic for controlling each of said branches.

6. In combination, a stretch of single track, signals located at intervals for governing traific in one direction through the stretch and other signals located at intervals for governing traflic in the other direction through the stretch, a track relay for the control of each signal, a circuit for each track relay each of which circuits is controlled by a front contact of the track relay for the next signal in advance governing traffic in the same direction, a branch for each track relay circuit which is not controlled by the front contact of the track relay which controls such circuit, and means controlled by traific in the direction governed by the signal controlled by the track relay circuit to control said branch.

7. In combination, a stretch of single track, signals located at intervals for governing trafiic in one direction through the stretch and other signals located at intervals for governing trafiic in the other directions through the stretch, a track relay for the control of each signal, a circuit for each track relay each of which circuits includes a front contact of the track relay for the next signal in advance governing traffic in the same direction, a branch for each track relay circult around the front contact of the track relay which controls such circuit, auxiliary relays for the control of said branches, and circuits for the control of said auxiliary relays controlled by said track relays.

8. In combination, a stretch of single track, signals located at intervals for governing traflic in one direction through the stretch and other signals located at intervals for governing traflic in the other direction through said stretch, a track relay for the control of each signal, a circuit for each track relay each of which circuits is energized in response to the energized condition of the track relay for the next signal in advance governing traffic in the same direction, and to the deenergized condition of the track relay for the opposing signal governing traiiic in the other direction; a branch circuit for energizing each track relay circuit which is not responsive to the energized condition of track relay which controls such circuit, and means energized in response to trailic in the directions governed by the signal controlled by the track relay to control said branch.

9. In combination, a stretch of track, a first first signal and a second signal for governing trafiic in one direction over said stretch, a track relay for controllirue, each signal arranged that the signal indicates proceed when its track relay is energized, means for energizing the track relay of the second signal when the track relay of the first signal is energized, and traflic controlled means for energizing the track relay of the second signal irrespective of the energization of the track relay of the first signal when a train travels in the direction for which said first and second signal governs trafiic, but which means are inefiective to energize said track relay of the second signal when a train travels in the opposite direction.

10. In combination, a stretch of single track, signals located at intervals for governing traffic in one direction through the stretch and other signals located at intervals for governing traific in the other direction through the stretch, a polarized track relay for the control of each signal and arranged to display 2. proceed indication when said relay is energized with one polarity of current and to display a caution indication when said relay is energized with the reverse polarity of current, a circuit for energizing each track relay with current of the first mentioned polarity each of which circuits includes a front neutral contact of the track relay for the next signal in advance governing traific in the same direction, a branch for each track relay circuit which controls such circuit for energizing the said circuit with current of the reverse polarity, and means controlled by the traific in the direction governed by the signal controlled by the track relay circuit for controlling said branch.

11. In combination, a single track railroad on which traific moves in both directions arranged in track sections, an advance track section and a rear track section for a given direction of travel, a track relay for each track section arranged that the energization of the track relay for the rear track section is dependent upon the energization of the track relay of the advance track section, a signal to govern traffic through the rear track section in the given direction and adapted to indicate proceed upon the energization of the track relay of said rear section, and additional means to effect the energization of the track relay of said rear section irrespective of the track relay of the advance section when a train travels from the rear section into the advance section but which means is not effective when a train travels from the advance section into the rear section.

12. In combination, a railroad on which traflic moves in both directions arranged in track sections, an advance track section and a rear track section when considering a given direction of travel, a track circuit for each of said track sections having a source of current and a track relay and arranged that the circuit for the rear section includes a front contact of the relay of the circuit of the advance track section, a signal for said rear section adapted to indicate proceed in response to current flowing in the track relay of said rear section, and trafiic controlled means responsive to a train passing from the rear track section into the advance track section to close the track circuit of the rear section around the front contact of the track relay of the advance section to thereby supply current to the circuit of the rear section and produce a caution signal indication, but which means is unresponsive to a train passing from the advance section into the rear section.

13. In combination, an advance track section and a rear track section, a track circuit including a track relay for each section, a slow release relay and a stick relay associated with the track relay of the advance track section, and arranged that said slow release relay is energized when said track relay of the advance section is energized, a pick-up circuit for said stick relay including a front contact of said slow release relay and a back contact of said track relay, a holding circuit for said stick relay including its own front contact and a back contact of said track relay, means rendered efiective to energize the track circuit of the rear track section when said stick relay is picked up, and a signal controlled by the track circuit of said rear section.

14. In combination, a stretch of track, a first signal and a second signal for governing trailic in one direction over said stretch; a polarized track relay for controlling each signal, arranged that the signal indicates proceed when its track relay is energized by one polarity, caution when said relay is energized by the reverse polarity and stop when said relay is deenergized; means rendered effective when the track relay of the first signal is energized to energize the track relay of the second signal with a polarity to produce a proceed signal indication, and traffic controlled means effective for energizing the track relay of the second signal with a polarity to produce a caution indication when a train travels in the direction for which said first and second signal governs trafiic, but which means is inefiective to energize said track relay of the second signal when a train travels in the opposite direction.

15. In combination, a railroad on which trafiic moves in both directions arranged in track sections, a first track section and a second track section, a track circuit for each of said track sections, means responsive to current in the track circuit of the first track section to establish the continuity of the track circuit of the second track section and to break the continuity of said circuit for the second section in response to the presence of a train in said first section, and traific controlled means responsive to a train passing from the second track section into the first track section to establish the continuity of the said track circuit for the second track section irrespective of the first mentioned means, said trafiic controlled means being unresponsive to establish the continuity of the circuit for said second section when a train passes from the first section into the second section, and a signal to control traific through said second section and controlled by the said track circuit of the second section.

16. In combination, a portion of track, normally inefiective means located at each end of said portion of track for supplying track circuit current to the track, means controlled from a central despatching office to selectively render effective one of said means to supply current to the track, means controlled by traffic conditions on another portion of track to govern the polarity of the current supplied to the track, and signals to govern traflic through said portion of track controlled by the track circuit current thus supplied.

1'7. In combination, a portion of track, normally inefiective means located at each end of said portion of track for supplying track circuit current to said track, relays located at each end of said portion of track and controlled from a central despatching ofiice to selectively render effective one of said means to supply current to the track, means controlled by traffic conditions on another portion of track to govern the polarity of the current supplied to the track, and

signals to govern trailic through: said portion of track controlled by the track circuit current thus supplied.

18'. In combination, a portion of track, nor mally ineife'ctive means located at each end of said portion of. track for supplying: track: circuit currentto. the track, means controlledv fromv a central. despatching oilice to render effective the means at one end or: the other of said portion of track to. supply current to the track, means controlled by traffic. conditions in. advance. of said portion of track to govern the polarity of the current supplied to the track, and signals to govern trafiic through said portion. of track controlled by the: track circuit current thus supplied.

19. Incombination, a portion of. track, a battery located at. each end of said portion of track for supplying track circuit current to. the: track and. normally inefiective to supply current to the. track, relays. controlled from a central despatching. oifice to selectively render efiective one of said. batteries to supply current" to the track, arelay controlled by trafli'c conditions on. another portion of track. to govern the polarity of thecurrent supplied'by said: battery, and signals to govern traffic through saidportion of track controlled by the track-circuit current thus supplied;

20; In combination, a track section, a normal.- ly deenergized track relay located at each. end of. said section,. and each. normally connected to the track, a battery located at each end of said trackisection to supply current to the track, but each normally ineffective to supply current, a dispatcher controlled relay associated with each end of the section, means controlled. by each despatcher controlled relay when energized to disconnect. the track relay from thetrack. at that end of. the section and to render the battery located at that end of the section effective to supply current to the track to thereby energize the: track. relay located. at the opposite end of the section, and signaling, means under the control of the track relays.

21. In combination, an insulated track seotion over which trafiic normally moves in both directions, signals to govern traflic in opposite directions through said. section, each normally indicating stop; two normally deenergized track circuits for said section, one associated. with the signal. governing traffic in. one direction and the other associated with the. signal governing trafhc in theopposite direction; a normally deenergized dispatcher controlled relay for each direction, and means controlled by each dispatcher controlled relay when energized to selectively energize the track circuit for the corresponding direction to thereby clear the signalv with. which said energized circuit is associated.

22. In combination, an insulated. track section over which trafiic normally moves in both directions, signals to govern. traffic in the opposite directions through said section, each normally indicating stop, two normally deenergized polarized track circuits for said. section, one: associated with the signal governing traffic in one direction and. the other associated. with the signal governing; traific in the opposite direction; despatcher. controlled means to selectively energize one of said track circuits; means controlled by traflic conditions: in another track section to govern the polarity of the track: circuit selected, said energization and polarity of said track circuit to eiTect a proceed indication of the signal with which said track circuit is selected.

23. In combination, an insulated track section over which traffic normally moves in both directions, signals to govern traiiic in opposite directions through said section each normally indicating stop, two normally deenergized track circuits for. said section, one for controlling the signal governing trafiic in one direction and the other for" controlling the signal governing traffic in the opposite direction,.and manually controlled. means associated with each end of the section effective when energized to selectively energize the track circuit associated with the signal at the opposite end of the section.

24. In combination, an insulated track section overwhich traffic normally moves in both directions, signals to govern trafiic in opposite directime through said-section, two normally deenergized track circuits for said section, one for controlling the signal governing trafiic in one direction. and the other for controlling the signal governing traflic in the opposite direction, and a despatcher controlled relay associated with each end of the section effective when energized to selectively energize the track circuit associated with the signal at the opposite end of the section.

25.v In combination, an insulated track section over which trafiic normally moves in both directions, signals'to govern traflic in the opposite directionsthrough said section, two normally deenergized polarized track circuits for said section, one associated with the signal governing traflic' in one direction and the other associated with the signal governing traflic in the opposite direction, despatclier controlled means to selectively govern said signals and to selectively energize the track circuit associated with thesignal selected, and automatically controlled means to govern the polarity of the track circuit. selected.

26.111 combination, an insulated track section over which traflic normally moves in both directions, two normally d-eenergized' polarized track circuits associated'with said track section, one for each direction of travel, despatcher controlled means to selectively energize the said track circuits otsaid section, automatically controlled means to govern the polarity of the track circuit selected, and a signal controlled by the said track circuit. selected.

2'7. In combination, an. insulated track section over which traflic normally moves in both directions, two normally deenergized polarized track circuits associated with said track section, one foreach direction of travel, despatcher controlled means to selectively energize the said track circuits of said. section, automatically controlled means to govern the polarity of the track. circuit selected, and signals under the joint control of the despatcher controlled means and the track circuits.

28'. In combination, traific rails arranged in track sect-ions, two normally deenergized track circuits for each trackv section including one for each direction each of which circuits includes the traflic rails in series, a relay manually controlled from a central despatching ofiice for each direction, and means controlled by each said relay when energized to selectively energize the track circuits for the corresponding direction.

29. In combination, traffic rails arranged in track. sections, two normally deenergized polarized track circuits for a track section each of which circuits includes the traific rails in'series,

means controlled from a central despatching' office to selectively energize one or the other of said track circuits, and traffic controlled means to govern the polarity of the track circuit selected.

30. In combination, trafiic rails arranged in track sections, two normally deenergized polarized track circuits for a given track section each of which circuits include the trafiic rails in series, despatcher controlled means to selectively energize said track circuits, means controlled by traffic conditions in another track section to govern the polarity of the track circuit selected, and signals controlled by said track circuits.

31. In combination, trafiic rails over which traflic normally moves in both directions arranged into insulated track sections, two normally deenergized polarized track circuits associated with a given track section, one for each direction of travel, despatcher controlled means to selectively energize the said track circuits of said given track section, automatic means under the control of. traflic in another track section to govern the polarity of the track circuit selected, and signals under the joint control of the despatcher controlled means and said track circuits.

32. In combination, a stretch of railway over which traflic normally moves in both directions said stretch being divided into at least three track sections, a first signal normally indicating stop associated with each section to govern trafiic in one direction, a second signal normally indicating stop associated with each section to govern trafiic in the opposite direction; two means to control the clearing of each of the three or more signals governing trafllc in one direction, one means being a track circuit, and the sec-- ond means being apparatus controlled from a central despatching office; and means to check the stop indication of the signals governing traffic in one direction through said stretch before the signals governing trafiic in the opposite direction can be cleared.

33. In combination, a stretch of railway over which trafiic normally moves in both directions and including a switch of a first passing siding, intermediate track and a switch .of a second passing siding, said stretch being divided into at least three track sections, a first signal normally indicating stop for each section to govern traffic in one direction, a second signal normally indicating stop for each section to govern traific in the opposite direction; two means to control the clearing of each of the three or more signals governing trafiic in one direction one means being a track circuit, and the second means being apparatus controlled from a central despatching oflice; and means to check the stop indication of the signals governing traffic in one direction through said stretch before the signal governing traflic in the opposite direction can be cleared.

34. In combination, a stretch of railway over which traffic normally moves in both directions, a first set of signals located at intervals to govern the passage of trains through said stretch in one direction, a second set of. signals located at intervals to govern the passage of trains through said stretch in the opposite direction, despatcher controlled means for selectively clearing either the first or the second set of signals, and traffic controlled means to check the stop in dication of each of the signals of the opposing set before the signals of the set selected can be cleared.

35. In combination, a stretch of railway over which traific normally moves in both directions,

a first set of signals located at intervals and each signal normally indicating stop to govern the passage of trains through said stretch in one direction, a second set of signals located at intervals and each signal normally indicating stop to govern the passage of trains through said stretch in the opposite direction, despatcher controlled means for selectively clearing either said first or second set of signals to permit the passage of a train, and traffic controlled means to check the stop indication of each of the signals of the opposing set before the signals of the set selected can be cleared.

36. In combination, a stretch of railway over which traffic normally moves in both directions, said stretch being divided into at least three track sections; a signal at each end of each section, two normally deenergized track circuits for the intermediate section of said three sections, one track circuit when energized being effective to clear the signals at one end of said section and at one end of the adjacent end section to permit a trafiic movement in one direction, and the other track circuit when energized being effective to clear the signals at the other end of said intermediate section and of the other end section to permit a traific movement in the other direction; and means controlled from a central despatching ofiice to selectively energize either one or the other of the track circuits of said intermediate track section.

37. In combination, a first intermediate track section, a second intermediate track section, a track relay associated with the first track section and normally connected to the track, a track relay associated with the second track section and normally connected to the track, means for at times selectively energizing one track relay or the other, a source of power associated with both first and second track sections, means under control of the track relay for the second track l section to disconnect the track relay for the first track section and to connect the source of power to said first section, a signal at each end of each section for governing trafiic movements through the section, means for energizing the signal at one end of a section when said source of power is applied to the track of the respective section, and means energizing the signal at the other end of a section when the track relay for the respective section is energized.

38. In combination, a first intermediate track section, a second intermediate track section, a track relay associated with the first track section and normally connected to the track, a track relay associated with the second track section and normally connected to the track, means for at times selectively energizing one track relay or the other, a source of power associated with both first and second track sections, means under the control of the track relay for the first track section to disconnect the track relay for the second track section and to connect the source of power to said second section, means under the control of the track relay for the second track section to disconnect the track relay for the first track section and to connect the source of power to said first section, and a signal at each end of each section for governing traflic movements through the section, one said signal being under the control of the track relay for the section and the other said signal: being under the control of said source of power..

39 In combination, a first intermediate track section, a. second intermediate. track section adijacent said first section, a track relay normally connected with. the first track; section, a. track relaynormally connected with the second track section, means forat times selectively energizing one track relay or the other, a source of power, meansunder the: control. of the track. relay for'the first track; section. to. disconnect the relayfor the second? track. section and toconnect the'source of power to said second section, means under the control of the track relay for the second track section to disconnectthe': track relay for the first track scctionandv to connect. the

' source 01: power to said: first. track section, and

two signals located at the junction of said: sections including a first signal under the: control of the track relay for the first track section for governing traific throughv said. first section, and a; second signal under the control of' the track relay for the second track section for governing: trafiicthrouglr saidseconct section.

40; In combination, a first intermediate track section, a. second intermediate: track section, a track relay" for each of. said track. sections. a stick relay for; each of; said track sections,. a source of current, means under the: control of the track. relay of the first: track section for disconnecting, under: certain: traific conditions;v the track'relay ofithe: second tracktsection andto-conheat the source ofpowen'theretoz-witha given poxlarity;,means under thecontrolof the stick. relay of the: first track section" for: disconnectingi'under certain other tra-Iiic conditions the track relay of; the second track: sectionsand to: connect the: source of. power thereto with: a. polarity reversed to said. given polarity;..and a. signal to govern trafiic through: said second track section controlled by the. current thus: supplied-to. said second track section;

41. In combination, a first intermediate track section, a second intermediate track: section, a rack relay for each of said track sections, a signalf oreaclr of said: tracksections to. govern traffic through: said sections; a: first circuit,. including aback contact of the'trackt relay-oi: the: second track. section, to connect the track relay of lhefirst trackisection.acrossthe rails of said first section; a second: circuit,'. includingxa backcontact of the track relayof' the first: track. section, to connect the track. relay of. the second track section across. the railsofsaid. second section; a. proceed signal circuit, including a front. con,- tact of the: track relay of the first track section, for" the: signal governing trafii'c: through said. first track section; and another proceed signal circuit, including a: front contact of the track relay'of the secondtrack circuit for thesignal governing: traffic through said secondtracl'c section 42.: In combination, a first track section,.a second track. section, a short. track section located between said first and second track sections, a track: relay for each of? said. three: mentioned track sections and each normally connected; to the track, means: under'the control of'the track relay of thefirst track sectionior di'sconnectingunder certain. trafiic conditions; the trackirelay'of the second track. section, .means under: the" control of the trackrelay of. thexsecond tracksectionzfor disconnecting, under certain otherttraflic conditions, the track relay of the first track section'andmeans under the: control of the. track: relayofi the short track? section; for controlling the: connections: 01' both the track: relays forthe firstand secondsecrtions to their respective track sections.

43. lin combination, a track section including a main: section and a subsidiary section located at the entrance of said: track section, a. track. relay for: said. main section, a track relay" for said. subsidi'ary section, a. slow-release relay energized when; both. said; track, relays areenergized, a stick relay a1. picleup circuit for said. stick relay including: albackcontact'; of each of said. trackrelays and a: front contact of said slow-release relay, a; holding: circuit. for: said; stick relay including its .own front" contact. and? a back contact of the track relay for the main-section, and signaling means under the control of said stick relay.

4.4.. Inzcombination, a,- first'passing'siding;asecs 0nd passing siding; a first tracka'section and a second? track section located between: said? passing: sidings with their outside" ends' adjacent the passing sidings, a source: ottrack: current and a track relay-Iocatedat each end of saidtrack secti'ons, two despa'tchcr controlled. relays including one at each siding each opera'bl'e to: selectively connect either the source of current or'the track relay across the rails of the first and second track sections: at their respective ends adjacent the sidings according as such relay is: energized or deenergized, traffic controlled means to selectively connect either the source; ofcurrent or-the track relay across the rails of said track sections: at their respective ends away from: said sidings, and signaling means controlled 'by said track relays;

45. Incombination, a stretch of'railway-including' a first passing siding and intervening track and extending to a second passing siding; said stretch'being' arrangedin track sections, each of which'is provided with a normally d'eene-rgi'zed trackcircuit, a signal to govern the-movement of a train-from the said first passing siding into said" intervening track, means for clearing said signal uponthe successive energization of all the normally deenergized track" circuits existing between said second siding and said" signal, and a dcspatcher controlled relay" adjacent said second siding operable when energizedto-eflect' said successive energization of said track circuits; 7 46'. In combination, a rear'track section, a forward track section, a first signal located" at the junction of saidtrack sectionsto govern tra-filc through saidforwardtrack section, a second" signal located to the rear of the-rear track section to govern tra-ifi'cthrough said rear track section, a normally deenerg-ized track relay to control the first signal, a normally deenergized track circuit for the rear track section to control the second signal; and a despatcher" controlled relay operable when energized toefl'ectenergization of said traclt relay to thereby clear said first signal and to: effect energization of said-track circuit to thereby clearsaid" second signal. 7

47; Incombination, a stretch of railway over which trafiic normally moves in either'di'rection, a first set of signals 'located at intervals to govemtrains through thestretchin one direction, a second set of'signalslocated at'intervals' to govern trains through the stretch in the opposite directien so arranged that there is a signal of the second set located adjacent eaclisignalof the-first set, d'espatcher controlled means to selectively control said first and second set of signals arranged to c'lear the signals of a set by starting attheremote end of the stretch and clearing the signals. successively; and traflic': controlled meansito-check; the: stop indication of the oppose ing signal adjacent each of the successive signals of the set selected before that signal can be cleared.

48. In combination, a stretch of railway over which traflic normally moves in either direction, a first 'set of signals located at intervals to govern the passage of trains through the stretch in one direction, a second set of signals located at intervals to govern the passage of trains through said stretch in the opposite direction, despatcher controlled means for selectively clearing either the first or second set of signals, and traflic controlled means to check the stop indication of each of the opposing set of signals before the final signal of the selected set can be cleared.

49. A railway signal system including a stretch of railway, a first set of signals located at intervals to govern traflic in one direction through the stretch, a second set of signals located at intervals to govern traific in the opposite direction through the stretch, a track circuit for each signal responsive to traflic conditions in advance of the signal, and a manually controlled means to establish the direction of trafiic adapted to cooperate with the track circuits to selectively clear one or the other of said sets of signals and operating to clear the signals of the selected set by starting at the remote end and clearing the signals successively.

50. A railway signal system including, a stretch of railway, a first set of signals located at intervals to govern traflic in one direction through the stretch, a second set of signals located at intervals to govern trafiic in the opposite direction through the stretch, a track circuit for each signal responsive to trafiic conditions in advance of the signal, and a manually controlled directional means adapted to also govern the track circuits to selectively clear one or the other of said sets of signals and arranged to permit the manually controlled directional means to reverse the direction of traific to the rear of a train as it occupies an intermediate point of the stretch and thereby permit traific in the reverse direction from said intermediate point.

51. A railway signal system including a stretch of railway, a first set of signals located at intervals to govern traffic in one direction through the stretch, a second set of signals located at intervals to govern traffic in the opposite direction through the stretch, a control circuit for each signal responsive to traflic conditions in advance of the signal, and a manually controlled directional means adapted to cooperate with the control circuits to selectively clear one or the other of said sets of signals and arranged to clear the signals of the selected set by starting at the remote end of the stretch and clearing the signals successively'and thereby permitting the reversing of the direction of trafiic to the rear of a train as it occupies an intermediate point of the stretch and the clearing of the opposing set of signals up to said intermediate point.

52.. A railway signal system including, a stretch of railway, a first set of signals located at intervals to govern trafiic in one direction through the stretch, a second set of signals located at intervals to govern traffic in the other direction through the stretch, a track circuit for-each signal responsive to trafiic conditions in advance of the signal, and a manually controlled directional means adapted to also govern the track circuits to selectively clear one set or the other of said set of signals and arranged to permit the manuallycontrolled directional means to reverse the direction of trafiic to the rear of a train but not in advance of a train as it occupies any intermediate point of the stretch and thereby permit traffic in the reverse direction from said train but not towards said train.

53. A railway signal system including, a stretch of railway, a first set of signals located at intervals to govern trafilc in one direction through the stretch, a second set of signals located at intervals to govern traflic in the opposite direction through the stretch, a control circuit for each signal responsive to trailic conditions in advance of the signal and to the condition of the control circuit for the signal in advance, and a manually controlled means associated with each direction of traflic each adapted to cooperate with the control circuit for the most remote signal of the corresponding set of signals to clear that signal and thereby clear each successive signal of the set serially.

54. In combination, a stretch of railway track provided with a traffic governing circuit connecting two trafiic governing relays respectively associated with opposite directions of trafiic and which circuit is normally short-circuited, a source of current associated with each direction of traffic for supplying current to said circuit but both normally disconnected therefrom, a signal normally indicating stop located at each end of the stretch to govern trafiic in opposite directions through the stretch, a control circuit for each signal having two normally open contacts, a first circuit controller governed from a central dispatching oiifice for closing one of said open contacts of the control circuit for a signal, a second circuit controller governed from the central dispatching office for removing the short circuit of the traffic governing circuit and for connecting therewith the current source associated with the direction of traflic governed by said signal for energizing the relay associated with that direction of traflic, and means controlled by said traffic governing relay when energized to close the other contact of the control circuit for said signal.

55. In combination, a stretch of railway track provided with a traffic governing circuit connecting two traflic governing relays respectively associated with opposite directions of traffic and which circuit is responsive to traific conditions in the stretch, a current source associated with each directionof trafiic for supplying current to said circuit but both normally disconnected therefrom, a signal normally indicating stop located at each end of the stretch to govern trafiic in opposite directions through the stretch, a control circuit for each signal having two normally open contacts, means controlled by the energization of the traffic governing relay associated with the direction of traffic which is governed by a signal for closing one of said open contacts of the control circuit of that signal, a first means controlled from a central dispatching oflice for closing the second open contact of said control circuit, a second means controlled from the central dispatching oflice to connect the current source associated with the direction of trafiic governed by that signal with the trafiic governing circuit for energizing the associated traffic governing relay and thereby establishing the direction of trafific, and means to prevent the central oflfice dispatching means from establishing more than one direction for traific at a time.

56. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing trainc in one direction and signals for governing traflic in the other direction through said section, a relay for controlling each signal included in a circuit including a front contact of the relay for the next signal in advance and including a back contact of the relay for an adjacent signal governing trafiic in the opposite direction, and manually controllable means for permitting relays controlling signals for governing traflic in one of said directions to be held at stop.

57. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing traffic in one direction and signals for governing traffic in the other direction through said section, a relay for each signal, a tumble down circuit for each direction of trafiic comprising a plurality of link-circuits each linkcircuit of which includes one of said relays and is controlled by the relay of the next link-circuit in advance, and means for interlocking each link of one tumbledown circuit with one link of the other tumble-down circuit in such manner that if one tumble-down circuit is energized all the links of the other tumble-down circuit are deenergized.

58. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing traific in one direction and signals for governing traific in the other direction through said section, a relay for each signal, a tumble-down circuit for each direction of traflic each comprising successive link-circuits one for each relay and each link-circuit controlled by the next link circuit in advance, and means for interlocking individually the link-circuits of said tumble-down circuits.

59. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing traflic in one direction and signals for governing trafiic in the other direction through said section, a relay for each signal, a tumble-down circuit for each direction of trafiic each comprising successive link-circuits one 'for each relay and each link-circuit controlled by the next link-circuit in advance, means for interlocking the link-circuits individually of said tumble-down circuits, and means for manually controlling said tumble-down circuits.

60. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing traffic in one direction and signals for governing traflic in the other direction through said section, a relay for each signal, a tumble-down circuit for each direction of traffic each comprising successive link-circuits one for each relay and each link-circuit controlled by the next link-circuit in advance, and a back contact of the relay for one link circuit included in the adjacent link-circuit for the opposite direction of traffic.

61. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing trafiic in one direction and signals for governing traific in the other direction through said section, a relay for each signal, a tumble-down circuit for each direction of trafiic each comprising successive link-circuits one for each relay and each link-circuit controlled by the next link circuit in advance, and means for interlocking the link-circuit for one direction of traflic with the adjacent link-circuit for the opposite direction of traffic.

62. In a signaling system for single track railroads, the combination with a single track section connecting two double track sections, of signals for governing traffic in one direction and signals for governing trafiic in the other direction through said section, a relay for each signal, a tumble-down circuit for each direction of traflic each comprising successive link-circuits one for each relay and each link-circuit controlled by the next link-circuit in advance, means for interlocking the link-circuit for one direction of tramc with the adjacent link-circuit for the opposite direction of traiiic, and other means for interlocking said tumble-down circuits.

EARL M. ALLEN. 

